Abstract
Administration of 1, 3-diaryl-1-nitrosoureas (I) prolonged the life span of rats inoculated intraperitoneally with ascites hepatoma AH13 cells. Active species produced from compound I were aryl diazonium ion, aryl isocyanate and nitrosonium ion. These species reacted with adenine, guanine, L-lysine, and the SH group of N-acetyl-DL-penicillamine. A possible anti-AH13 action mechanism of 1, 3-diaryl-1-nitrosoureas in proposed to be as follows. The nitrosoureas (I) permeate quickly into the cytoplasm or nucleus, and decompose to give an active intermediate, an aryl diazonium ion, which reacts with nucleic acids of tumor cells to form a deoxyribonucleic acid (DNA) adduct, followed by tumor cell death. DNA repair of other damaged cells is inhibited by aryl isocyanate and nitrosonium ion liberated from compound I, which reacts with repair enzyme to form carbamoylated and S-nitrosated enzyme.
